The present invention relates broadly to cargo pallets, collapsible containers, and fixed wall containers and, more particularly, to a molded cargo support device having curved recesses formed therein to accept lifting implements.
When transporting cargo, such as food and other supplies for shipboard, industrial or commercial use, it is common practice to stack the cargo on pallets or within standard containers that are made of wood or other suitable material. Unless specifically stated otherwise herein, with respect to the present invention, the terms pallet and container are generally interchangeable, as the present invention has application with both pallets and containers, both collapsible and fixed-wall. Therefore, for clarity, the term “pallet” will be employed herein and should be generally understood to encompass both pallets and pallet boxes, also known as containers, both collapsible and fixed-wall, and with distinctions being made when necessary.
When cargo loaded onto the pallet must be lifted, such as when loading it onto a ship, or vehicle bed, a crane will usually be used to lift the pallet. The interface between the pallet and a crane hook can include straps, chains, cables, round bars, tubes or combinations thereof for pallet engagement.
Such a wooden pallet is illustrated in FIG. 6, labeled prior art, which depicts a cross section of a wooden pallet 50 that includes top pallet planks 52, bottom pallet planks 54 and joiner boards 56. The way the joiner boards 56 are placed intermediate the top and bottom pallet planks 52, 54, creates a cavity 58 at the end of the pallet 50. Therefore, one or more of the various lifting devices described above may be fitted within the cavities and the pallet raised by the crane. When the wood pallets and associated corrugated boxes are empty, they are generally ground up and discarded at sea.
In order to eliminate this waste, it would be desirable to provide a pallet that is formed from polymer material which may be reused. Such reusable cargo support devices should be compatible with wooden pallets, thereby giving rise to several requirements for the reusable pallet. First, the reusable cargo support device should have the ability to be handled in the same manner that the wooden pallets are handled. They also need to work with the wooden pallets during handling.
One method of cargo handling involves the use of a “straddle truck.” The straddle truck has a body supported well off the ground by elongate legs to define a cargo handling space under the body and between the legs. The straddle truck also includes two generally L-shaped arms that project down from the truck body into the cargo handling space. The arms are laterally movable for pallet gripping, and vertically movable for pallet lifting.
The straddle truck driver sits about ten feet off the ground and the entire truck generally has enough height from the ground up to the truck frame to clear a two-high stack of 39 inch tall containers or pallets, or to accommodate a 40″ container and 26″ container, stacked. Arms of the straddle truck are laterally displaceable from a disengaged position to a position wherein horizontally projecting members projecting from the arms engage the cavities 58 in the pallets. Accordingly, any substitute would necessarily have to provide some form of spacing for straddle truck engagement.
Once the straddle truck delivers the pallets to the dock, the pallets are hoisted onto the supply ship decks or on vehicle beds. They can be hoisted using slings, cables or steel bars and straps, accommodated by the cavity 58 in the wooden pallet 50.
The pallets are also used to get supplies from a supply ship to another ship during underway replenishment. When this occurs, the transfer at sea can be done using different methods. One method includes the ships moving side by side. There, a cable system is erected between the ships and the goods are transferred via high line using the cable system. Another way is to use helicopters to move the cargo from one ship to another. Once again, straps, slings or other lifting elements are provided to move the pallet between ships on the high line or via helicopter, with the lifting elements engaging the cavities in the pallets. All such devices, including the straddle truck engaging members, configured for engaging a cargo support device for lifting may be collectively referred to herein as “lifting support implements”. The use of this term is for clarity and is not intended to limit the present invention in any way.
Accordingly, there exists a need for a usable cargo support device that can be moved in the manner of a wooden pallet and can work freely with the same systems as a wooden pallet, with or without wooden pallets present.